Section 74
SEC. 74. Leases under the provisions of this Act shall be for a period not exceeding twenty-five years from the date of the execution of the lease contract, and shall be renewable under such terms and conditions as may be provided by law for another period not exceeding twenty-five years. The total period of any lease and the extension thereof shall not exceed fifty years. Such leases shall provide that the lessee may at any time during the life of the lease apply for the cancellation of the same, and surrender the property leased whenever, because of force majeure, or for other causes, it is impossible to continue profitable mining operations thereon. No such lease or renewal thereof shall be assigned or sublet without the prior consent of the Secretary of Agriculture and Commerce which shall be granted if the assignment or sublease is to such persons, associations, or corporations as have the qualifications required of locators, holders, or lessees under the provisions of this Act.